Dr Reichenbach on Petroleum or Mineral Oil. 377 



smell of petroleum became at once distinctly perceptible. I re- 

 peated this process eight times with fifty kilograms of coal, and 

 when I had united the fluids obtained, separated the oil and 

 rectified it without adding any mixture whatever, I found that 

 the quantity of oil amounted to 150 kilograms. This proportion 

 would give one loth of oily fluid to the Austrian cwt. of coal. 



As the amount obtained in this manner was so small, I caused 

 a vessel to be filled in the coal-pit with newly quarried coal, had 

 it well closed and brought to the surface, and immediately sub- 

 jected its contents to the process of distillation. The oil it 

 afforded was decidedly more abundant, but it did not exceed 

 the double of that obtained from the usual coal exposed for sale 

 in magazines. 



Upon more minute examination, the oil exhibited the follow- 

 ing properties. 



It was perfectly clear and transparent, had a light greenish- 

 yellow tint of colour, which would probably have disappeared 

 on second distillation ; it was extremely fluid, and had com- 

 pletely the smell of a tolerable pure natural naphtha. The taste 

 was the same as that of white petroleum. The specific gravity at 

 a temperature of 20° Cent, was 0.836, therefore agreeing in this 

 respect with the petroleum of Amiano as described by Saussure. 

 In the open air it evaporated pretty rapidly, and its boiling point 

 was 167° C. ; thus nearly that of the Persian naphtha, which 

 Thomson gives as 160° C. 



Light and air, or the rays of the sun, produced in the oil no 

 perceptible alteration. It could, however, be inflamed without 

 the use of a wick, and could be made to burn upon the whole 

 surface, giving at the same time a strong light, and having the 

 same thick sooty smoke as petroleum. 



Upon placing the oil and the ordinary petroleum of commerce 

 under bell-shaped glasses, each separate and mixed with iodine, 

 both attracted iodine vapours from the air and became brownish- 

 red. On the other hand, the iodine took the oil vapours from 

 the air, and became blended with it. The oils after some time 

 became thick, and then clear again at the same time after the de- 

 position of a small portion of a dark iodine combination. 



Powdered sulphur was dissolved in certain quantities by cold 

 oil as by petroleum ; when heated, the quantity dissolved wjts 



